Walking beam chamber

ABSTRACT

Disclosed is a device fabrication system comprising a wafer input loadlock, a wafer output loadlock, one or more wafer processing regions, and one or more walking beams for transporting one or more wafers from the wafer input loadlock through the wafer processing regions, and onto the wafer output loadlock. Also disclosed are methods for transporting one or more wafers through the device fabrication system described herein.

FIELD OF THE DISCLOSURE

Embodiments of the present disclosure relate generally to devicefabrication systems, and is more particularly concerned with a walkingbeam chamber design, and methods for transporting wafers therein.

BACKGROUND OF THE DISCLOSURE

Processing wafers may involve a sequence of similar or differentprocedures such as etching, thin film deposition, cleaning and so on.The processing steps may be performed in a single device fabricationsystem including a plurality of distinct processing chambers. The wafersmay be transported from one processing chamber to another. The amount ofwafers processed through a fabrication system reflects its throughput.Existing device fabrication systems with discrete processing chambersarranged radially around a transfer chamber have an upper limit in termsof number of wafers that can be processed per hour.

SUMMARY OF THE DISCLOSURE

In certain embodiments, the instant disclosure may be directed to adevice fabrication system comprising a wafer input loadlock, a waferoutput loadlock, one or more wafer processing regions, and one or morewalking beams for transporting one or more wafers from the wafer inputloadlock through the wafer processing regions, and onto the wafer outputloadlock.

In other embodiments, the instant disclosure may be directed to a methodfor transporting one or more wafers. The method may comprise unloading aprocessed wafer into a wafer output loadlock by transporting one or morewafers through wafer processing regions in an output row with a thirdwalking beam. The method may further comprise transporting a wafer froman input row to the output row with a second walking beam. The methodmay further comprise loading a new wafer from a wafer input loadlockinto a wafer processing region in an input row by transporting one ormore wafers through wafer processing regions in the input row with afirst walking beam.

In a further embodiment, the instant disclosure may be directed to amethod for transporting one or more wafers. The method may comprisetransporting a new wafer from a wafer input loadlock into a waferprocessing region by transporting one or more wafers through a row ofwafer processing regions with a walking beam that is indexed to shiftthe one or more wafers to a next position.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is illustrated by way of example, and not by wayof limitation, in the figures of the accompanying drawings in which likereferences indicate similar elements. It should be noted that differentreferences to “an” or “one” embodiment in this disclosure are notnecessarily to the same embodiment, and such references mean at leastone.

FIG. 1 depicts a top view of existing device fabrication systems withquad chambers.

FIG. 2 depicts an illustration of a walking beam mechanism.

FIG. 3 depicts a top view of a device fabrication system with a walkingbeam mechanism according to an embodiment.

FIGS. 4A-4F illustrate a process for transporting a wafer through adevice fabrication system with a walking beam mechanism according to anembodiment.

DETAILED DESCRIPTION

With an ever increasing demand for semiconductor devices, devicefabrication systems that reduce wafer processing time, reduce waferprocessing chamber loading and unloading time, and increase waferthroughput while also being cost effective are beneficial. The presentdisclosure is directed to an architecture of a device fabrication systemthat allows for device processing in a continuous and efficacious mannerthat increases wafer throughput, reduces cost, enables improved serviceaccess and gas distribution, takes up less space, is compatible withexisting wafer processing equipment, and is suitable for implementing avariety of processes. The device fabrication system in embodimentsincludes a large chamber that is approximately rectangular shaped, witha first dimension being orders of magnitude longer than a seconddimension. The device fabrication system includes many processingregions. The device fabrication system uses one or more walking beammechanisms to transport wafers between the processing regions. Certainembodiments of this disclosure may be described in further detail belowwith respect to the figures.

As used herein, the singular forms “a,” “an,” and “the” include pluralreferences unless the context clearly indicates otherwise. Thus, forexample, reference to “a wafer” includes a single wafer as well as amixture of two or more wafers; and reference to a “wafer processingchamber” includes a single wafer processing chamber as well as a mixtureof two or more wafer processing chambers, and the like.

As used herein, the term “about” in connection with a measured quantity,refers to the normal variations in that measured quantity, as expectedby one of ordinary skill in the art in making the measurement andexercising a level of care of one skilled in the art and the precisionof the measuring equipment. In certain embodiments, the term “about”includes the recited number±10%, such that “about 10” would include from9 to 11.

As used herein, the term “transporting” refers to the actions of liftingand carrying an article (e.g., a wafer, a carrier, a carrier with awafer) from one place to another place with the direction of a walkingbeam.

As used herein, the term “loading” refers to introduction of a new waferinto a wafer processing chamber.

As used herein, the term “unloading” refers to taking away a processedwafer from a wafer processing chamber.

Recitation of ranges of values herein are merely intended to serve as ashorthand method of referring individually to each separate valuefalling within the range, unless otherwise indicated herein, and eachseparate value is incorporated into the specification as if it wereindividually recited herein. All methods described herein can beperformed in any suitable order unless otherwise indicated herein orotherwise clearly contradicted by context. The use of any and allexamples, or exemplary language (e.g., “such as”) provided herein, isintended merely to illuminate certain materials and methods and does notpose a limitation on scope. No language in the specification should beconstrued as indicating any non-claimed element as essential to thepractice of the disclosed materials and methods.

FIG. 1 is a top plan view showing a conventional device fabricationsystem 100 including a loading and storing apparatus 110, a factoryinterface 115, and a load lock 120 positioned adjacent a conventionalprocessing tool 130. A factory interface (FI) 115 is shown positionedbetween the loading and storing apparatus 110 and load lock 120. The FI115 includes an FI robot (not shown) that may move in FI 115 and mayextract a wafer from the loading and storage apparatus 110. The FI robotmay bring the wafer to a load lock 120. A main frame (MF) robot locatedat MF 140 (also referred to herein as a transfer chamber) may carry thewafer from load lock 120 to a processing chamber, such as quadprocessing chamber 152, 154, or 156. The MF robot may place the waferinto a processing region in a wafer receiving area of quad processingchamber 152, 154, or 156. The MF robot may have an upper blade and alower blade and each blade may have two fingers. This design allows a MFrobot to pick up two wafers at a time.

A typical loading and unloading sequence with a device fabricationsystem as depicted in FIG. 1 may include an FI robot in FI 115extracting a first wafer from a loading and storage apparatus 110 (e.g.,a front opening unified pod (FOUP)) and placing it in a loadlock 120.The FI robot may subsequently extract a second wafer from the loadingand storage apparatus 110 and place it next to the first wafer in theloadlock 120. A MF robot may pick up the first and the second wafers,carry them to quad chamber 152, and load them in two wafer receivingareas 152A and 152B in respective wafer processing regions. Thereafter,quad chamber 152 may move the two wafers in wafer receiving areas 152Aand 152B to wafer processing regions in the back so that the MF robotcan access wafer receiving areas 152C and 152D. Each quad processchamber (152, 154, and 156) may have a carrousel design therein. Thecarrousel design allows rotation of the wafer receiving areas betweenwafer processing regions within each quad chamber. In this manner, eachwafer receiving area within each quad chamber may be positioned in thefront row at a certain time (at first and second wafer processingregions), making them accessible to the MF robot, being that the MFrobot cannot directly access the rear two quad chamber wafer processingregions. In the meantime, the FI robot extracts two additional wafersfrom the loading and storage apparatus 110 and carries them to theloadlock 120 where the MF robot picks up the two additional wafers andbrings them to quad chamber 152 into wafer receiving areas 152C and 152Dat the front two wafer processing regions.

When all wafer receiving areas (and all of the wafer processing regions)in the quad chamber are filled, the quad processing chamber may beginprocessing the wafers at each of the wafer processing regions. In someinstances, processing the wafer may involve moving the wafer receivingareas between multiple wafer processing regions to average outnon-uniformities and improve process performance. Once processing iscomplete, the MF robot may unload processed wafers from the quad chamberand replace them with new wafers. The MF robot may bring the processedwafers to the loadlock and swap them for new wafers at the loadlockagain.

Once quad chamber 152 is fully loaded, the process may repeat itselfwith the other quad chambers (154 and 156) by positioning wafers inwafer receiving areas 154A, 154B, 154C, 154D, 156A, 156B, 156C, and 156Dof the quad chambers 154, 156.

The duration for fully loading each quad chamber could add up to about40 seconds in duration per quad chamber. Although the above descriptionwith respect to FIG. 1 depicts a plurality of quad chambers (chambersincluding four wafer processing regions), some fabrication systems mayhave chambers with less or more wafer processing regions therein (e.g.,twin chambers with two wafer processing regions in each or chambers withsix wafer processing regions in each). The duration for fully loadingeach twin chamber may include the swap time (i.e., the time it takes aMF robot to swap and load two new wafers and unload two processedwafers). The swap time may be about 13 second. The existing quad chambermay be less efficient than the twin chamber because its loading andunloading time encompasses the time that it takes to move the stations(i.e., the wafer receiving areas) within the quad chamber. Chambers withmore than two wafer processing regions with a similar mechanism mayexhibit a similar inefficiency as that seen in the quad chamber.

In some instances, the time it takes to load and unload wafers in eachquad chamber may start to exceed wafer processing time. It may take moretime to stop chamber processing to get wafers in and out of the quadchamber than to process the wafers in the wafer processing chamberswithin a quad chamber. There have been attempts to make the MF robotoperate faster in order to reduce the loading and unloading time.However, the challenge with long loading and unloading time remains. Theadded time for loading and unloading the processing chambers andprocessing the wafers may amount to a throughput of about 400 wafers perhour in some instances. It is beneficial to reduce the wafer loading andunloading times to increase throughput. The device fabrication systemsdescribed herein may be used without an MF robot altogether.Accordingly, in embodiments expense associated with the MF equipment,the MF space 140 space associated with the MF robot, and time associatedwith actions conventionally performed by a MF robot may be reduced oreliminated.

In embodiments, rather than using a MF connected to separate processingchambers, each having its own environment, a single large processingchamber may be used that transports wafers between wafer processingregions using a walking beam mechanism. Existing systems as describedwith reference to FIG. 1 operate as “single input single output” and“stop/start” systems. In contrast, the processing system described inembodiments uses a walking beam mechanism that would enable a continuouswafer processing flow.

Embodiments described herein set forth a new type of processing chamberthat uses a walking beam mechanism to transport wafers between waferprocessing regions. Multiple walking beam mechanisms may be used in someembodiments.

FIG. 2 depicts a walking beam mechanism that may be used to index wafersthrough a series of wafer processing regions in a device fabricationsystem according to an embodiment. The walking beam mechanism may have aconcept that is similar to that of a conveyor belt. However, a conveyorbelt design would not hand off a wafer to a processing region. Incontrast, a walking beam would hand off the wafer to a wafer processingregion as it may lift the wafer from one wafer processing region, indexit over to the next wafer processing region, and then optionally lowerit onto the next wager processing region. In FIG. 2, walking beam 210may transport all wafers 212, 214, 216, 218, and 220 simultaneously frompositions 252, 254, 256, 258, and 260, respectively, to their nextindexed position, e.g., one over to positions 254, 256, 258, 260, and262, respectively. Exemplary methods of transporting wafers across awafer processing chamber (e.g., between wafer processing regions in theprocessing chamber) using the walking beam mechanism of FIG. 2 in thedevice fabrication system described herein is further described withrespect to FIGS. 4A-4F below.

FIG. 3 is a top plan view showing a device fabrication system 300according to an embodiment. The device fabrication system may have arectangular shape, with a length that is many times longer than a width.The device fabrication system may include two or more rows of waferprocessing regions 351-365. For example, as shown wafer processingregions 351-355 are in an input row 356, and wafer processing regions361-365 are in an output row 366. Though two rows of wafer processingregions are shown, a single row may be used, or more than two rows maybe used.

Device fabrication system 300 may comprise a wafer input loadlock 350 inline with input row 356 and a wafer output loadlock 360 in line withoutput row 366. Each of input row 356 and output row 366 may compriseone or more wafer processing regions, such as wafer processing regions351, 352, 353, 354, and 355 in input row 356 and wafer processingregions 361, 362, 363, 364, and 365 in output row 366. The wafer inputloadlock 350 and the wafer output loadlock 360 may be coupled to inputrow 355 and output row 365, respectively (e.g., bolted together).Similarly, each of the processing regions in input row 355 and in outputrow 366 may be coupled to each other (e.g., bolted together or to acommon floor or support structure).

Wafer input loadlock 350 and wafer output loadlock 360 may be positionedlaterally on the same plane. In certain embodiments, the wafer inputloadlock 350, wafer output loadlock 360, input row 356, and output row366 may all be on the same plane.

Wafer processing regions 351-355 in input row 356 and wafer processingregions 361-365 in output row 366 may be together enclosed in a commonelongated chamber 340. The processing regions may be arranged to performconventional device fabrication processes such as chemical vapordeposition, physical vapor deposition, atomic layer deposition, etching,cleaning, oxidation, thin film deposition, heat treatment, degassing,cool down, etc. Some processing regions may be configured to perform thesame type of process (e.g., multiple wafer processing regions mayperform deposition processes). Additionally, different wafer processingregions may perform different types of processes. For example, a firstwafer processing region may be configured to perform ALD processes,while a second wafer processing region may be configured to performphysical vapor deposition processes, and/or a third wafer processingregion may be configured to perform oxidation processes. In someembodiments, the processing regions are configured to perform devicefabrication processes under vacuum. In an embodiment, all processingregions enclosed in the common elongated chamber share the same interiorvolume of the elongated chamber. Accordingly, the processing regions mayshare a common pressure. Similarly, all processing regions may shareother commonalities, such as, without limitations, cooling water, power,and the like.

In an example, a processing region (such as processing regions 351-355and 361-365 in FIGS. 3-4F) may include a wafer support assembly, anelectrostatic chuck (ESC), a ring (e.g., a process kit ring or singlering), a chamber wall, a base, a gas distribution plate, a showerhead,gas lines, a nozzle, a lid, a liner, a liner kit, a shield, a plasmascreen, a flow equalizer, a cooling base, a chamber viewport, a chamberlid, and so on.

In one embodiment, the processing region includes a body and ashowerhead that enclose an interior volume. The showerhead may include ashowerhead base and a showerhead gas distribution plate. Alternatively,the showerhead may be replaced by a lid and a nozzle in someembodiments. The body may be fabricated from aluminum, stainless steelor other suitable material. The body generally includes sidewalls and abottom. An outer liner may be disposed adjacent the sidewalls to protectthe body.

An exhaust port may be defined in the body, and may couple the interiorvolume to a pump system. The pump system may include one or more pumpsand throttle valves utilized to evacuate and regulate the pressure ofthe interior volume of the processing region. The interior volume of theprocessing region may not be sealed off from an interior volume of theelongate processing chamber that contains the processing region.

The showerhead may be supported on the sidewall of the body. A gas panelmay be coupled to the processing region to provide process and/orcleaning gases to the interior volume through the showerhead (or a lidand nozzle). The wafer support assembly is disposed in the interiorvolume of the processing region below the showerhead or lid. The wafersupport assembly holds the wafer during processing. A ring (e.g., asingle ring) may cover a portion of the electrostatic chuck, and mayprotect the covered portion from exposure to plasma during processing.The ring may be silicon or quartz in one embodiment.

An inner liner may be coated on the periphery of the wafer supportassembly. The inner liner may be a halogen-containing gas resistantmaterial such as those discussed with reference to the outer liner. Inone embodiment, the inner liner may be fabricated from the samematerials as those of outer liner.

Returning to FIG. 3, device fabrication system 300 may further compriseone or more walking beams 370, 380, and 390 for transporting one or morewafers through the wafer processing regions 351-355 and 361-365 inaccordance the mechanism described with respect to FIG. 2. In anembodiment, a first walking beam 370 may be suitable for transportingone or more wafers from wafer input loadlock 350 and through the waferprocessing regions 351-355 in input row 356. A second walking beam 380may be suitable for transporting a wafer from input row 356 to outputrow 366 (e.g., from wafer processing region 355 to wafer processingregion 365). A third walking beam 390 may be suitable for transportingone or more wafers through the wafer processing regions 365-361 inoutput row 366 and finally onto wafer output loadlock 360. Each walkingbeam may be operated by an actuator.

In certain embodiments, the walking beam and the actuator may beenclosed in the common elongated chamber along with all of the waferprocessing regions. In other embodiments, the walking beam and theactuator may be outside the common elongated chamber. In furtherembodiments, the walking beam may be inside the common elongated chamberalong with all of the wafer processing regions and the actuator may beoutside the common elongated chamber.

The design of the walking beam and their actuator is not limited and mayinclude, for instance, one or more of shafts, bellows, linear motors,linear bearings, magnets, and so on. In one embodiment, the walking beamand actuator mechanism may comprise one or more shafts on each side ofthe common elongated chamber. The shafts may be isolated from the commonelongated chamber environment (e.g., vacuum or corrosive gases) usingbellows. The shafts may slide in a forward and backward direction via amechanism that may optionally reside outside the common elongatedchamber. In other embodiments, the walking beam and actuator maycomprise two bars tied together and coupled to a linear motor to movethe bars. In certain embodiments, linear bearings and linear motors maybe utilized to move a walking beam enclosed along with the processingregions in the common elongated chamber. In some embodiments, alevitated linear motor may be used to move the walking beam (e.g., whenit is enclosed in a high vacuum environment in a common elongatedchamber).

In certain embodiments, each wafer processing region may have a separatewalking beam and actuator as opposed to a common walking beam andactuator for the entire row of wafer processing regions. Similarly, insome embodiments, a plurality of wafer processing regions (e.g., two,three, and so on) may have a common walking beam and actuator. Thevariations in walking beam positions and/or designs may provide waferprocessing flexibility. For instance, a walking beam may be programmedto transport the wafer into certain wafer processing regions whileskipping certain other wafer processing regions.

In some embodiments, each wafer may undergo processing in each and everyone of the wafer processing regions in the device fabrication system. Inanother embodiment, a wafer may undergo processing in certain waferprocessing regions and skip other wafer processing regions. Theprocessing route that each wafer may take through the fabrication systemmay depend, among other factors, on the length of the walking beam, itsposition, its design, its actuator, and how it is programmed totransport a wafer among the wafer processing regions (i.e., the indexedposition of each wafer).

The processing of each wafer may be split up across a plurality of waferprocessing regions. Some or all wafer processing regions may operatesimultaneously. For example, each of the wafer processing regions351-365 may perform a respective process (e.g., a deposition process,etch process, etc.) on a different wafer concurrently. Another examplemay be where the wafer undergoes deposition of a layered stack ofdifferent materials. The wafer may have one material deposited in onewafer processing region and another material deposited in another waferprocessing region and so on. The systems described herein enable aplurality of wafers to be processed simultaneously. The designs of thedevice fabrication systems described herein may be customized to aparticular process. For example, an entire sequence of processes may beperformed on a collection of wafers that move through the devicefabrication system 300. Accordingly, the single device fabricationsystem 300 may be a replacement to a traditional device fabricationsystem that includes a transfer chamber coupled to multiple quadchambers, single chambers, and/or dual chambers.

If different processes with incompatible chemistries occur in adjoiningwafer processing regions, it may be possible to generate a gas curtainshield to avoid cross-contamination between the wafer processingregions. Gas curtain shields may be generated by flowing gas through anarea separating adjacent wafer processing regions to catch contaminantparticles (and optionally plasmas, gases, etc.) in the gas so that theseparticles (and optionally plasmas, gases, etc.) do not contaminate theadjacent wafer processing regions. Cross-contamination may also bereduced by purging and pumping (i.e., drawing into vacuum incompatiblegases and replacing them with inert gas shields).

In certain embodiments, the wafers transported through the waferprocessing chambers may be temporarily mounted on carriers and the oneor more walking beams may interface with and transport the carriersalong with the wafers thereon.

One of the advantages of device fabrication system disclosed hereinincludes its adaptability to existing processing equipment. Forinstance, the device fabrication system described herein may be usedwith a pedestal heater having an electronic chuck positioned thereon, ashower head above the pedestal heater and electronic chuck, and radiofrequency (RF) delivery system further on top, as is used in someexisting device fabrication systems. In certain embodiments, standardchamber lifts (e.g., lift pins) may be used for the vertical motionassociated with lifting a wafer from a wafer processing region onto acarrier of a walking beam and/or lowering the wafer from the carrier ofthe walking beam onto the wafer processing region.

In certain embodiments (not shown in the figures), the one or more waferprocessing regions may all be in a single row having a wafer inputloadlock at one end of the row and a wafer output loadlock at anotherend of the row. In this embodiment, one or more walking beams maytransport one or more wafers from the wafer input loadlock, through thewafer processing regions, and finally to the wafer output loadlock. Withthis arrangement, the wafer input loadlock, wafer processing regions,and wafer output loadlock may all be arranged in one line and on oneplane.

In other embodiments (not shown in the figures), the one or more waferprocessing regions may be arranged in three rows. A wafer input loadlockmay be positioned at a first end of a first row. A wafer output loadlockmay be positioned at the first end or at an opposite end of a second rowor third row. A first walking beam may move wafers between processingregions in the first row. A second walking beam may move wafers betweenprocessing regions in the second row. A third walking beam may movewafers between processing regions in the third row. A fourth walkingbeam may be positioned at the first end and may move wafers between thefirst, second and/or third rows. Additionally or alternatively, a fifthwalking beam may be positioned at the opposite second end and may movewafers between the first, second and/or third rows.

In other embodiments (not shown in the figures), the one or more waferprocessing regions may be arranged in four rows. A wafer input loadlockmay be positioned at a first end of a first row. A wafer output loadlockmay be positioned at the first end or at an opposite end of a secondrow, a third row, or a fourth row. A first walking beam may move wafersbetween processing regions in the first row. A second walking beam maymove wafers between processing regions in the second row. A thirdwalking beam may move wafers between processing regions in the thirdrow. A fourth walking beam may move wafers between processing regions inthe fourth row. A fifth walking beam may be positioned at the first endand may move wafers between the first, second, third and/or fourth rows.Additionally or alternatively, a sixth walking beam may be positioned atthe opposite second end and may move wafers between the first, second,third and/or fourth rows. In one embodiment, the fifth walking beam ispositioned at the second end (far end from the input load lock) andmoves wafers from the first row to the second row. In this embodiment,the sixth walking beam is positioned at the first end (near end to theinput load lock) and moves wafers from the second row to the third row.In this embodiment, a seventh walking beam is positioned at the secondend (far end from the input load lock) and moves wafers from the thirdrow to the fourth row. The output loadlock may be on the first end of afourth row.

In order to allow for continuous wafer processing through waferprocessing regions (e.g., 351-355 and 361-365), the common elongatedchamber 340 may be separated from the wafer input loadlock and the waferoutput loadlock. In an embodiment, the common elongated chamber (e.g.,340) is separated from the wafer input loadlock (e.g., 350) with inputslit valve (e.g., 342) and from wafer output loadlock (e.g., 360) withoutput slit valve (e.g., 344). Such an arrangement may enable continuouswafer processing without having to stop wafer processing and restartwafer processing each time a new wafer is placed into the wafer inputloadlock and a processed wafer is removed from the wafer outputloadlock. The slit valves may effectively isolate the common elongatedchamber 340 from the wafer input loadlock 350 and from the wafer outputloadlock 360. This isolation may enable maintenance of a controlledenvironment in the common elongated chamber, such as a controlledpressure and temperature.

Device fabrication system 300 may further comprise a factory interface(FI) 330 similar to that of a conventional device fabrication system(such as factory interface 115 in system 100 of FIG. 1) and a loadingand storing apparatus 320 (such as apparatus 110 in system 100 in FIG.1). FI 330 may include a FI robot that may extract new wafers fromloading and storing apparatus 320 and place them into wafer inputloadloack 350. The FI robot may also remove processed wafers from waferoutput loadlock 360 and bring them to loading and storing apparatus 320.

FI 330 may be separated from wafer input loadlock 350 with input door332 and from wafer output loadlock 360 with output door 334. The doorsmay effectively isolate the wafer input loadlock, wafer output loadlock,and common elongated chamber 340 (when the input slit valve and/oroutput slit valve are open) from the FI. This isolation may enablemaintenance of a controlled environment in the common elongated chamber,such as a controlled pressure, moisture and/or temperature.

The device fabrication systems described herein may comprise any numberof wafer processing regions ranging from 1 to 50, from 2 to 40, from 3to 30, from 4 to 24, from 4 to 20, from 6 to 20, from 6 to 16, from 8 to16, from 8 to 12, or any single number or range in between. In anembodiment where all wafer processing regions are arranged in one row,the number of wafer processing regions may be odd or even. In anembodiment where the wafer processing regions are arranged in two rows(i.e., input row and output row as shown in FIG. 3), the number of waferprocessing regions will likely be even.

Each wafer processing region may have dimensions of about 22″×22″, about23″×23″, about 24″×24″, about 26″×26″, about 28″×28″, about 30″×30″,about 34″×34″, and so on in some embodiments. The dimensions of a commonelongated chamber enclosing all wafer processing regions may becalculated based on the dimensions of each wafer processing region andthe total number of wafer processing regions. In certain embodiments(e.g., as depicted in FIG. 3), the common elongated chamber may have alength of about 120″ (24″ per wafer processing region×5 wafer processingregions per row) and a width of about 48″. These dimensions are merelyexemplary and should not be construed as limiting.

The footprint of the device fabrication systems described herein mayencompass the space taken by the loading and storing apparatus, factoryinterface, wafer input loadlock, wafer output loadlock, and commonelongated chamber (enclosing the wafer processing regions). The systemsdescribed herein may have a smaller footprint and save space as comparedto conventional device fabrication systems of the type depicted in FIG.1 by excluding a MF body and a MF robot. Removing the MF content mayalso reduce cost that would otherwise be expended on volume and hardwarefor the MF (e.g., minimum number of slit valves may be used, no MFrobot, no MF body).

The continuous wafer processing sequence in the device fabricationsystem of FIG. 3 may be described in further detail with respect toFIGS. 4A-4F. To start, walking beams 370, 380, and 390 may be enclosedalong with wafer processing regions 351-355 and 361-365 in the commonelongated chamber 340. Walking beam 370 may be positioned over waferprocessing regions 351-355. Walking beam 380 may be positioned alongwafer processing region 365 in output row 356. Walking beam 390 may bepositioned along wafer processing regions 361-365. This may be referredto as the “starting position” for each of the walking beams 370, 380,and 390 in the description below.

Referring to FIG. 4A, output slit valve 344 may open. Walking beam 390may unload a processed wafer into a wafer output loadlock 360. This mayoccur by the walking beam transporting all five wafers (or carriers withor without wafers in case any of the carriers is empty) in waferprocessing regions 365, 364, 363, 362, and 361 and transporting them allover simultaneously to the next indexed position. For instance, the nextindexed position may have all the wafers transported to the nextadjacent wafer processing region in the output row (i.e., into waferprocessing regions 364, 363, 362, 361, and wafer output loadlock 360).Referring to FIG. 4B, walking beam 390 may return back to the startingposition where it may be enclosed along with the wafer processingregions in the common elongated chamber 340 and may be positioned alongwafer processing regions 361-365.

Referring to FIGS. 4C-4D, walking beam 380 may transport a wafer (orcarrier with or without a wafer) from wafer processing region 355 ininput row 356 to the next indexed position (i.e., into wafer processingregion 365 in output row 366).

During this time, an FI robot may extract a new wafer from loading andstoring apparatus 320, and bring the new wafer into wafer input loadlock350 through open input door 332. After placing the new wafer into waferinput loadlock 350, the FI robot may remove the processed wafer fromwafer output loadlock 360 via output door 334.

In the meantime, input door 332 may close and the pressure in waferinput loadlock 350 may be pumped down to reach a vacuum. Once thepressure in wafer input loadlock 350 reaches the same value as thepressure level of the common elongated chamber 340, input slit valve 342may open. Referring to FIG. 4E, walking beam 370 may then load the newwafer from the wafer input loadlock into a wafer processing region inthe input row. This may occur by the walking beam transporting all fivewafers (or carriers with or without wafers in case any of the carriersis empty) in wafer input loadlock 350 and in wafer processing regions351, 352, 353, and 354 to the next indexed position. For instance, thenext indexed position may include transporting all the wafers by one asshown in FIG. 4F (i.e., into wafer processing regions 351, 352, 353,354, and 355).

In certain embodiments, the method for transporting one or more wafersthrough the device fabrication systems described herein may comprisetransporting a new wafer from a wafer input loadlock into a waferprocessing region. The transporting may occur by having a walking beamlift and carry one or more wafers simultaneously to the next indexedposition in a row of wafer processing regions.

The methods described herein may operate when all wafer processingregions have wafers being processed therein as well as when some but notall wafer processing regions have wafers being processed therein. Forinstance, when the wafer processing regions in the common elongatedchamber are empty, the methods described herein may be followed togradually populate one or more of the wafer processing regions.Initially, a first new wafer may be placed in the wafer input loadlockby an FI robot. The walking beam mechanism may lift the first wafer andcarry it over to the next indexed position (which may be the immediatelyadjoining wafer processing region). Thereafter and while the first waferis being processed in its wafer processing region, the FI robot mayplace a second wafer in the wafer input loadlock and the walking beammechanism may lift the first and the second wafer simultaneously andcarry them to the next indexed position. This process may repeat itselfcontinuously to further load additional new wafers to be processed inthe wafer processing regions. Unlike in existing chambers (such as thequad chamber), wafers that are inside a wafer processing region may beprocessed while a new wafer gets introduced into the wafer inputloadlock and thereafter into the common elongated chamber. Waferprocessing does not stop for introduction of new wafers or for removalof processed wafers. The same actions may be performed whether thecommon elongated chamber is fully loaded, stagger loaded, every otherwafer processing region is loaded, empty, or in any other arrangement.

The continuous nature of the wafer transport method described herein mayimprove the wafer throughput. Wafer throughput of systems describedherein may be related to the indexing time associated with transportinga wafer from one position to the next indexed position (using thewalking beam mechanism) and the wafer processing time. For instance,with the device fabrication system depicted in FIGS. 3-4F and a transfertime of about 5 second between wafer processing regions, the throughputcould reach about 720 wafers per hour.

In some embodiments, the transfer time of transporting a wafer from onewafer processing region to another is about 10 second or less, about 8second or less, about 6 seconds or less, about 5 seconds or less, about4 seconds or less, about 3 seconds or less, about 1 second to about 10seconds, about 1.5 seconds to about 8 seconds, about 2 seconds to about6 seconds, or any particular number or range in between, in duration.

In certain embodiments, the wafer transport method described hereincomprises processing about 450 or more, about 500 or more, about 550 ormore, about 600 or more, about 650 or more, about 700 or more, about 450to about 1000, about 500 to about 900, about 600 to about 800, or anyparticular number or range in between, wafers per hour.

The device fabrication systems disclosed herein may also provide forimproved service access and gas distribution. For instance,commonalities (such as common pressure, gas, cooling water, power andthe like) may be distributed to all wafer processing regions enclosed inthe common elongated chamber 340. For instance, gases may be distributedto the common elongated chamber 340 down the center and every region maybe accessed.

In certain embodiments, wafer processing regions with special designsmay also be incorporated into the device fabrication system. Forinstance, wafer processing region designs that incorporate a cup arounda heater and a top pumping interface may integrate well with a walkingbeam mechanism described herein.

Some wafer processes (e.g., thin film deposition) may deposit materialon chamber components and not only on the wafer itself. Cleaningprocesses may be implemented to remove such contaminants. Cleaningprocesses of the wafer processing regions and/or of the common elongatedchamber may also be implemented in the fabrication systems describedherein. For instance, cleaning may be performed by running a processwithout any wafers (skipping a wafer load). In some instances, an FIrobot may place a dummy wafer in the wafer input loadlock to load adummy wafer into the device fabrication system. A dummy wafer may beused when the top surface of the heater in a wafer processing region isto be protected. In some instances, the top surface of the heater in thewafer processing region need not be protected and a dummy wafer may notbe used during a cleaning process (the cleaning may occur by skipping awafer load for example).

In the foregoing description, numerous specific details are set forth,such as specific materials, dimensions, processes parameters, etc., toprovide a thorough understanding of the present disclosure. Theparticular features, structures, materials, or characteristics may becombined in any suitable manner in one or more embodiments. The words“example” or “exemplary” are used herein to mean serving as an example,instance, or illustration. Any aspect or design described herein as“example” or “exemplary” is not necessarily to be construed as preferredor advantageous over other aspects or designs. Rather, use of the words“example” or “exemplary” is simply intended to present concepts in aconcrete fashion. As used in this application, the term “or” is intendedto mean an inclusive “or” rather than an exclusive “or”. That is, unlessspecified otherwise, or clear from context, “X includes A or B” isintended to mean any of the natural inclusive permutations. That is, ifX includes A; X includes B; or X includes both A and B, then “X includesA or B” is satisfied under any of the foregoing instances. Referencethroughout this specification to “an embodiment”, “certain embodiments”,or “one embodiment” means that a particular feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment. Thus, the appearances of the phrase “anembodiment”, “certain embodiments”, or “one embodiment” in variousplaces throughout this specification are not necessarily all referringto the same embodiment.

The present disclosure has been described with reference to specificexemplary embodiments thereof. The specification and drawings are,accordingly, to be regarded in an illustrative rather than a restrictivesense. Various modifications of the disclosure in addition to thoseshown and described herein will become apparent to those skilled in theart and are intended to fall within the scope of the appended claims.

What is claimed is:
 1. A device fabrication system comprising: two ormore adjacent rows, wherein the two or more adjacent rows comprise: awafer input loadlock in line with an input row comprising one or morewafer processing regions; a wafer output loadlock in line with an outputrow comprising one or more wafer processing regions; and one or morewalking beams for transporting one or more wafers from the wafer inputloadlock, through the wafer processing regions, and onto the waferoutput loadlock.
 2. The device fabrication system of claim 1, whereinthe one or more walking beams comprise a first walking beam fortransporting one or more wafers through the wafer processing regions inthe input row, a second walking beam for transporting a wafer from theinput row to the output row, and a third walking beam for transportingone or more wafers through the wafer processing regions in the outputrow.
 3. The device fabrication system of claim 1, wherein the waferinput loadlock and the wafer output loadlock are positioned laterally onthe same plane.
 4. The device fabrication system of claim 1, wherein theone or more wafer processing regions are enclosed in a common elongatedchamber under a vacuum.
 5. The device fabrication system of claim 4,wherein the common elongated chamber is separated from the wafer inputloadlock and from the wafer output loadlock with an input slit valve andan output slit valve, respectively.
 6. The device fabrication system ofclaim 4, wherein the one or more walking beams are inside the commonelongated chamber.
 7. The device fabrication system of claim 4, whereinthe one or more walking beams are outside the common elongated chamber.8. The device fabrication system of claim 1, further comprising afactory interface that is separated from the wafer input loadlock andfrom the wafer output loadlock with an input door and an output door,respectively.
 9. The device fabrication system of claim 1, wherein theone or more wafer processing regions comprise one or more of a chemicalvapor deposition chamber, a physical vapor deposition chamber, an atomiclayer deposition chamber, or an etch process chamber.
 10. The devicefabrication system of claim 1, wherein one or more wafer processingregions, the wafer input loadlock, and the wafer output loadlock are onthe same plane.
 11. A method for transporting one or more wafers,comprising: unloading a processed wafer into a wafer output loadlock bytransporting one or more wafers through one or more wafer processingregions in an output row with a third walking beam; transporting a waferfrom an input row to the output row with a second walking beam, whereinthe input row and the output row are two adjacent rows; and loading anew wafer from a wafer input loadlock into a wafer processing region inan input row by transporting one or more wafers through one or morewafer processing regions in the input row with a first walking beam. 12.The method of claim 11, wherein each of the unloading the processedwafer, the transporting the wafer from the input row to the output row,and the loading the new wafer, are 10 seconds or less in duration. 13.The method of claim 12, processing about 450 or more wafers per hour.14. The method of claim 11, further comprising removing the processedwafer from the wafer output loadlock and placing the new wafer into thewafer input loadlock by a factory interface robot.
 15. The method ofclaim 11, wherein the first walking beam, the second walking beam, andthe third walking beam transport the one or more wafers by lifting themand carrying to a next indexed wafer processing region or to the waferoutput loadlock.
 16. The method of claim 11, wherein the waferprocessing regions in the input row and the wafer processing regions inthe output row comprise one or more of a chemical vapor depositionchamber, a physical vapor deposition chamber, an atomic layer depositionchamber, or an etch process chamber.
 17. A method for transporting oneor more wafers, comprising transporting a new wafer from a wafer inputloadlock into a wafer processing region by lifting and carrying one ormore wafers through two or more adjacent rows of wafer processingregions with two or more walking beams that are indexed to shift the oneor more wafers to a next position, wherein the wafer input loadlock anda wafer output loadlock are each in line with a respective row of thetwo or more adjacent rows.
 18. The method of claim 17, processing about450 or more wafers per hour.